A positron emission tomography study of oculomotor imagery

Lang, Wilfried; Petit, Laurent; Höllinger, Peter; Pietrzyk, U.; Tzourio, N.; Mazoyer, Bernard; Berthoz, Alain

doi:10.1097/00001756-199404000-00017

Cited by 80 publications

(31 citation statements)

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“…At the cortical level, these areas include the cortical eye fields (med-FEF, lat-FEF, SEF, and PEF) that previous functional neuroimaging studies agree in describing as involved in numerous saccadic eye movements (for a recent review see McDowell et al 2008) and occipital activations in the primary visual area extending to both ventral and dorsal extrastriate pathways. At the subcortical level, we observed both putamen and thalamus activations (Lang et al 1994;Law et al 1998;Petit and Beauchamp 2003;Petit et al 1993Petit et al , 1996 as part of the cortico-subcortical oculomotor loop initially described in the parallel-pathway hypothesis (Alexander et al 1986; see also McHaffie et al 2005).…”

Section: Discussionsupporting

confidence: 58%

Functional Asymmetries Revealed in Visually Guided Saccades: An fMRI Study

Petit¹,

Zago²,

Vigneau³

et al. 2009

Journal of Neurophysiology

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Mellet E, Tzourio-Mazoyer N. Functional asymmetries revealed in visually guided saccades: an fMRI study. J Neurophysiol 102: 2994 -3003, 2009. First published August 26, 2009 doi:10.1152/jn.00280.2009. Because eye movements are a fundamental tool for spatial exploration, we hypothesized that the neural bases of these movements in humans should be under right cerebral dominance, as already described for spatial attention. We used functional magnetic resonance imaging in 27 right-handed participants who alternated central fixation with either large or small visually guided saccades (VGS), equally performed in both directions. Hemispheric functional asymmetry was analyzed to identify whether brain regions showing VGS activation elicited hemispheric asymmetries. Hemispheric anatomical asymmetry was also estimated to assess its influence on the VGS functional lateralization. Right asymmetrical activations of a saccadic/attentional system were observed in the lateral frontal eye fields (FEF), the anterior part of the intraparietal sulcus (aIPS), the posterior third of the superior temporal sulcus (STS), the occipitotemporal junction (MT/V5 area), the middle occipital gyrus, and medially along the calcarine fissure (V1). The present rightward functional asymmetries were not related to differences in gray matter (GM) density/sulci positions between right and left hemispheres in the precentral, intraparietal, superior temporal, and extrastriate regions. Only V1 asymmetries were explained for almost 20% of the variance by a difference in the position of the right and left calcarine fissures. Left asymmetrical activations of a saccadic motor system were observed in the medial FEF and in the motor strip eye field along the Rolando sulcus. They were not explained by GM asymmetries. We suggest that the leftward saccadic motor asymmetry is part of a general dominance of the left motor cortex in righthanders, which must include an effect of sighting dominance. Our results demonstrate that, although bilateral by nature, the brain network involved in the execution of VGSs, irrespective of their direction, presented specific right and left asymmetries that were not related to anatomical differences in sulci positions.

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Section: Discussionsupporting

confidence: 58%

Functional Asymmetries Revealed in Visually Guided Saccades: An fMRI Study

Petit¹,

Zago²,

Vigneau³

et al. 2009

Journal of Neurophysiology

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“…No activation of the parietal cortex was seen in this case. The same three areas were activated when the subjects were asked to perform imaginary self-paced saccades in total darkness (Lang et al 1994).…”

Section: C On T R I Bu T Ion Of T H E Pa R I Eta L C Ort E X To T Hmentioning

confidence: 97%

Parietal and hippocampal contribution to topokinetic and topographic memory

Berthoz

1997

Phil. Trans. R. Soc. Lond. B

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146

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This paper reviews the involvement of the parietal cortex and the hippocampus in three kinds of spatial memory tasks which all require a memory of a previously experienced movement in space. The ¢rst task compared, by means of positron emission tomography (PET) scan techniques, the production, in darkness, of self-paced saccades (SAC) with the reproduction, in darkness, of a previously learned sequence of saccades to visual targets (SEQ). The results show that a bilateral increase of activity was seen in the depth of the intraparietal sulcus and the medial superior parietal cortex (superior parietal gyrus and precuneus) together with the frontal sulcus but only in the SEQ task, which involved memory of the previously seen targets and possibly also motor memory.The second task is the vestibular memory contingent task, which requires that the subject makes, in darkness, a saccade to the remembered position of a visual target after a passively imposed whole-body rotation. De¢cits in this task, which involves vestibular memory , were found predominantly in patients with focal vascular lesions in the parieto-insular (vestibular) cortex, the supplementary motor areaŝ upplementary eye ¢eld area, and the prefrontal cortex.The third task requires mental navigation from the memory of a previously learned route in a real environment (the city of Orsay in France). A PET scan study has revealed that when subjects were asked to remember visual landmarks there was a bilateral activation of the middle hippocampal regions, left inferior temporal gyrus, left hippocampal regions, precentral gyrus and posterior cingulate gyrus. If the subjects were asked to remember the route, and their movements along this route, bilateral activation of the dorsolateral cortex, posterior hippocampal areas, posterior cingulate gyrus, supplementary motor areas, right middle hippocampal areas, left precuneus, middle occipital gyrus, fusiform gyrus and lateral premotor area was found. Subtraction between the two conditions reduced the activated areas to the left hippocampus, precuneus and insula.These data suggest that the hippocampus and parietal cortex are both involved in the dynamic aspects of spatial memory, for which the name`topokinetic memory' is proposed. These dynamic aspects could both overlap and be di¡erent from those involved in the cartographic and static aspects of`topographic' memory.

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“…Ocular motor activity is reflected by signal increases in areas that correspond to FEF Petit et al, 1995;Lang et al, 1994), supplementary eye field (SEF; PierrotDeseilligny et al, 1993), and parietal eye field (PEF; Pierrot-Deseilligny et al, 1995). The activations in the basal ganglia can be attributed to the basal ganglia-thalamocortical (ocular) motor loop (Alexander et al, 1986).…”

Section: An "Exteroceptive Mental State" (Eyes Open ͼ Eyes Closed)?mentioning

confidence: 99%

Eye closure in darkness animates sensory systems

et al. 2003

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Single subject and group analyses (n ϭ 12) showed that the eyes-open and eyes-closed states in complete darkness considerably and consistently differ in the patterns of associated brain activation in fMRI. During nonchanging external stimulation, ocular motor and attentional systems were activated when the eyes were open; the visual, somatosensory, vestibular, and auditory systems were activated when the eyes were closed. These data suggest that there are two different states of mental activity: with the eyes closed, an "interoceptive" state characterized by imagination and multisensory activity and with the eyes open, an "exteroceptive" state characterized by attention and ocular motor activity. Our study also shows that the chosen baseline condition may have a considerable impact on activation patterns and on the interpretation of brain activation studies.

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A positron emission tomography study of oculomotor imagery

Cited by 80 publications

References 0 publications

Functional Asymmetries Revealed in Visually Guided Saccades: An fMRI Study

Functional Asymmetries Revealed in Visually Guided Saccades: An fMRI Study

Parietal and hippocampal contribution to topokinetic and topographic memory

Eye closure in darkness animates sensory systems

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